Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

`
`
gm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?m)^NAME=""(?P<name>(?P<disk>[a-z]+)(?P<partition>\d*))""\sFSTYPE=""(?P<fstype>\w*)""\sMOUNTPOINT=""(?P<mountpoint>[\w\[\]/]*)""\sSIZE=""(?P<size>\d*)""\sTYPE=""(?P<type>\w+)""$"; string input = @"NAME=""loop0"" FSTYPE=""LVM2_member"" MOUNTPOINT="" SIZE=""20971520000"" TYPE=""loop"" NAME=""sda"" FSTYPE="" MOUNTPOINT="" SIZE=""171798691840"" TYPE=""disk"" NAME=""sda1"" FSTYPE=""ext4"" MOUNTPOINT=""/boot"" SIZE=""1073741824"" TYPE=""part"" NAME=""sda2"" FSTYPE=""LVM2_member"" MOUNTPOINT="" SIZE=""170723901440"" TYPE=""part"" NAME=""sdb"" FSTYPE="" MOUNTPOINT="" SIZE=""32212254720"" TYPE=""disk"" NAME=""sdb1"" FSTYPE=""LVM2_member"" MOUNTPOINT="" SIZE=""32211206144"" TYPE=""part"" NAME=""sdc"" FSTYPE="" MOUNTPOINT="" SIZE=""53687091200"" TYPE=""disk"" NAME=""sdc1"" FSTYPE=""LVM2_member"" MOUNTPOINT="" SIZE=""53686042624"" TYPE=""part"" NAME=""sr0"" FSTYPE="" MOUNTPOINT="" SIZE=""1073741312"" TYPE=""rom"" NAME=""cl_ctos8auto-root"" FSTYPE=""xfs"" MOUNTPOINT=""/"" SIZE=""106300440576"" TYPE=""lvm"" NAME=""cl_ctos8auto-root"" FSTYPE=""xfs"" MOUNTPOINT=""/"" SIZE=""106300440576"" TYPE=""lvm"" NAME=""cl_ctos8auto-swap"" FSTYPE=""swap"" MOUNTPOINT=""[SWAP]"" SIZE=""8497659904"" TYPE=""lvm"" NAME=""cl_ctos8auto-home"" FSTYPE=""xfs"" MOUNTPOINT=""/home"" SIZE=""108536004608"" TYPE=""lvm"" NAME=""cl_ctos8auto-var_log"" FSTYPE=""ext4"" MOUNTPOINT=""/opt/imsdb/chroot-sybase/var/log"" SIZE=""32208060416"" TYPE=""lvm"" NAME=""b38ad718--fc07--11ea--9894--0050569ae644-fea1a18c--fc07--11ea--9894--0050569ae644"" FSTYPE=""ext4"" MOUNTPOINT=""/opt/intelerad/atlas/1/storage/b30f29df-8fc2-4db5-8c17-4275cdae6b3f"" SIZE=""20967325696"" TYPE=""lvm"""; RegexOptions options = RegexOptions.Multiline; foreach (Match m in Regex.Matches(input, pattern, options)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx